Origin

In Old English a daft person was mild and gentle, qualities which tougher folk have often interpreted as signs of foolishness or mental incapacity. Deft (Middle English) was a related word, which first meant ‘mild, meek’ as well as ‘skilful’. Daft came to refer to lack of intelligence during the Middle Ages, and from the 16th century it could also imply madness. It could also mean playfulness—the festivities of Christmas used to be referred to as the daft days. See also crazy, silly